I have this collection_select <%= collection_select(:template, :template_id, #templates, :id, :name) %> and I want to basically call :name.humanize, but obviously that doesn't work.
How can i call a method such as .humanize on an attribute of collection_select (a hash attribute?)
EDIT
Here's a snippet from my controller:
#templates = Template.select(:name).group(:name)
p "templates = #{#templates}"
Here's what appears in the console:
"templates = #<ActiveRecord::Relation:0x007f84451b7af8>"
With Rails 4
Just like this:
<%= collection_select(:template, :template_id, #templates, :id, Proc.new {|v| v.name.humanize}) %>
In the Proc block, v will be your models, iterated through a each loop.
collection_select works with anything that inherit from Enumerable and have no limit in the content of the Proc.
With Rails 3
You must do it your self, by preparing your data before passing it to collection_select
# This will generate an Array of Arrays
values = #templates.map{|t| [t.id, t.name.humanize]}
# [ [record1.id, record1.name.humanize], [record2.id, record2.name.humanize], ... ]
# This will use the Array previously generated, and loop in it:
# - send :first to get the value (it is the first item of each Array inside the Array)
# - send :last to get the text (it is the last item of each Array inside the Array)
# ( we could have use :second also )
<%= collection_select(:template, :template_id, values, :first, :last) %>
Related
Is there any way to use grouped_collection_select value_method with parameters in Rails?
I'm trying to filter out a couple of options based on the current_user (effectively using something like: signed_by(current_user)) but I'm having some difficulty passing it in.
<%= f.grouped_collection_select :author_id, Author.posts, :signed_by, :title, :id, :email %>
Any ideas?
It's not possible to pass parameters to the value_method in this case because the value_method option is "the name of a method which, when called on a child object of a member of collection, returns a value to be used as the contents of its tag". In other words, it's just a string or symbol that will get called on the Author.posts collection.
If you're trying to filter out some options, I would suggest filtering them from the collection, and then passing the filtered collection to this method. Something like:
# author_helper.rb
def filtered_author_posts
Author.posts.where.not(signed_by: current_user)
end
<%= f.grouped_collection_select :author_id, filtered_author_posts, :signed_by, :title, :id, :email %>
I got an error while trying to use collection_select ;)
I got this code in my view:
<%= f.collection_select(:channel, :channel_id, #channels, :id, :channelname, prompt: true) %>
in my controller I have this:
#channels = Channel.all
and I got this error:
undefined method `merge' for :channelname:Symbol
Whats my failure ?
Thanks at all!
According to the docs:
collection_select(method, collection, value_method, text_method,
options = {}, html_options = {}) public
So therefore you should use:
<%= f.collection_select(:channel_id, Channel.all, :id, :channelname, prompt: true) %>
You can use like
Channel.all.pluck(:id, :channelname)
For example take look at below
collection_select(
:post, # field namespace
:author_id, # field name
# result of these two params will be: <select name="post[author_id]">...
# then you should specify some collection or array of rows.
# It can be Author.where(..).order(..) or something like that.
# In your example it is:
Author.all,
# then you should specify methods for generating options
:id, # this is name of method that will be called for every row, result will be set as key
:name_with_initial, # this is name of method that will be called for every row, result will be set as value
# as a result, every option will be generated by the following rule:
# <option value=#{author.id}>#{author.name_with_initial}</option>
# 'author' is an element in the collection or array
:prompt => true # then you can specify some params. You can find them in the docs.
)
try this
<%= f.collection_select(:channel_id, :id, prompt: true) %>
I am using Cocoon gem to do nested forms.
I have models like that:
# request.rb
has_many :filled_cartridges, inverse_of: :request, dependent: :destroy
accepts_nested_attributes_for :filled_cartridges, :reject_if => :all_blank, allow_destroy: true
#filled_cartridge.rb
belongs_to :request
Inside of my form_for #request i have nested form like that:
<div id="filled_cartridges">
<%= f.fields_for :filled_cartridges do |filled_cartridge| %>
<%= render 'filled_cartridge_fields', f: filled_cartridge %>
<% end %>
<div class="links">
<%= link_to_add_association 'add', f, :filled_cartridges %>
</div>
Where filled_cartridge_fields partial is like that:
<fieldset>
<%= f.text_field :cartridge_id %>
<%= f.hidden_field :_destroy %>
<%= link_to_remove_association "remove", f %>
</fieldset>
When i click on "add" it adds one more . When clicking on "remove" it removes that .
When i submit form the params for nested form look like that:
filled_cartridges_attributes: !ruby/hash:ActionController::Parameters
'0': !ruby/hash:ActionController::Parameters
cartridge_id: '12'
_destroy: 'false'
'1429260587813': !ruby/hash:ActionController::Parameters
cartridge_id: '2'
_destroy: 'false'
How do i access these params, and how to save them. How to traverse over these params and save them, or do Cocoon gem has some built in functionality? And finally how to check if these params are set? Since it is nested, it tricks me.
EDIT: My request_controllers#create:
def create
#request = Request.new( request_params )
# code for handling Request model
# here i want to handle nested model too (filled_cartridge)
#request.save
if #request.save
flash[:success] = "Заявка была добавлена"
redirect_to #request
else
render 'new'
end
end
EDIT2: my strong params:
def request_params
params.require(:request).permit(:name, :address, :phone, :mobile, :type, :description, :priority, :responsible, :price, :payed, :date, filled_cartridges_attributes: [:cartridge_id, :_destroy], :stype_ids => [], :social_media =>[])
end
In a recent project using cocoon I had to access the params of the attributes about to be saved. I figured a code in my create action in my controller. The trick is to understand how to retrieve the key of the hash of the attribute that is about to be saved. The key of the hash is that number '1429260587813' that is in your params
...
'1429260587813': !ruby/hash:ActionController::Parameters
cartridge_id: '2'
_destroy: 'false'
So you need to create a loop in your create action to retrieve this key using ruby hash method "keys". I do a loop because when using cocoon dynamic nested field I might create more than one nested attributes at once so it means more than one key to retrieve.
Here is a the code that worked for me, read my comments which explains the different steps of this code. I hope it will help you to adapt it to your needs.
#Here I just initialize an empty array for later use
info_arr = []
#First I check that the targeted params exist (I had this need for my app)
if not params[:recipe]["informations_attributes"].nil?
#z variable will tell me how many attributes are to be saved
z = params[:recipe]["informations_attributes"].keys.count
x = 0
#Initiate loop to go through each of the attribute to be saved
while x < z
#Get the key (remember the number from above) of the first hash (params) attribute
key = params[:recipe]["informations_attributes"].keys[x]
#use that key to get the content of the attribtue
value = params[:recipe]["informations_attributes"][key]
#push the content to an array (I had to do this for my project)
info_arr.push(value)
#Through the loop you can perform actions to each single attribute
#In my case, for each attributes I creates a new information association with recipe
#recipe.informations.new(title: info_arr[x]["title"]).save
x = x +1
end
end
This work to access cocoon nested attribute content and apply actions based on your need. This worked for me so you should be able to use this sample code and adapt it to your need.
I have multiple identical collection selects inside a single form. I prefer this over a multiple select list for aesthetic and UX reasons. I have to use a terrible kludge to make everything work right, and I'm wondering if there is a more elegant way to do this:
From the view:
<% 3.times do |i| %>
<%= collection_select("selected_item_" + i.to_s.to_s, :name, #items, :name, :name, { :include_blank => true }, { id: "selected_item_" + i.to_s }) %>
<% end %>
From the controller:
ItemContainer = Struct.new(:name)
3.times do |i|
param = ('selected_item_' + i.to_s).to_sym
instance_variable = '#' + param_name
if params[param] && !params[param].empty?
#selected_items << params[param][:name]
instance_variable_set(instance_variable, ItemContainer.new(params[param][:name]))
end
end
#selected_channels.each.... # do what I need to with these selections
Most of these gymnastics are needed to ensure that the item is still selected if the page is refreshed. If there were some way to force collection select to use arrays, that would be the answer, but I couldn't make that work.
If I understang right you're looking for selegt_tag method (docs: http://api.rubyonrails.org/classes/ActionView/Helpers/FormTagHelper.html#method-i-select_tag)
You can write something like this
select_tag "people[]", options_from_collection_for_select(#people, "id", "name")
select_tag "people[]", options_from_collection_for_select(#people, "id", "name")
and it youd output two selects for people, which would be sent as an array on submit.
if you use the [] naming in your collection_select calls then the params will send over the data as an array
I am a bit confused as to the usage of collection_select here as it doesn't seem like you are using a model object? this example using select_tag - might be able to come up with something more appropriate to your issue if the model structures were known
# run this in the loop
# set selected_value to appropriate value if needed to pre-populate the form
<%= select_tag('name[]',
options_from_collection_for_select(#items, 'name', 'name', selected_value),
{ include_blank: true }
)
%>
in controller update/create action
# this works because the select tag 'name' is named with [] suffix
# but you have to ensure it is set to empty array if none are passed, usually only issue with checkboxes
names = params[:name] || []
names.each do |name|
puts name
end
side note: you can use string interpolation with ruby double quotes in places of + for string concatenation
<%= collection_select("selected_item_#{i}",
:name,
#items,
:name,
:name,
{ include_blank: true },
{ id: "selected_item_#{i}" }
)
%>
see also: http://apidock.com/rails/v3.2.13/ActionView/Helpers/FormOptionsHelper/options_from_collection_for_select
We're using the "serialize" feature of ActiveRecord in Rails like this:
class User < ActiveRecord::Base
serialize :favorite_colors, Array
....
end
So we can have
u = User.last
u.favorite_colors = [ 'blue', 'red', 'grey' ]
u.save!
So basically ActiveRecord is serializing the array above and stores it in one database field called favorite_colors.
My question is: How do you allow a user to enter his favorite colors in a form?
Do you use a series of textfields? And once they're entered, how do you show them in a form for him to edit?
This is a question related to Rails Form Helpers for serialized array attribute.
Thanks
If you want multi-select HTML field, try:
= form_for #user do |f|
= f.select :favorite_colors, %w[full colors list], {}, :multiple => true
If you're using simple_form gem, you can present the options as check boxes easily:
= simple_form_for #user do |f|
= f.input :favorite_colors, as: :check_boxes, collection: %w[full colors list]
I have solved this problem by 'flattening' the array in the view and
reconstituting the array in the controller.
Some changes are needed in the model too, see below.
class User < ActiveRecord::Base
serialize :favorite_colors, Array
def self.create_virtual_attributes (*args)
args.each do |method_name|
10.times do |key|
define_method "#{method_name}_#{key}" do
end
define_method "#{method_name}_#{key}=" do
end
end
end
end
create_virtual_attributes :favorite_colors
end
If you don't define methods like the above, Rails would complain about the form element's
names in the view, such as "favorite_colors_0" (see below).
In the view, I dynamically create 10 text fields, favorite_colors_0, favorite_colors_1, etc.
<% 10.times do |key| %>
<%= form.label :favorite_color %>
<%= form.text_field "favorite_colors_#{key}", :value => #user.favorite_colors[key] %>
<% end %>
In the controller, I have to merge the favorite_colors_* text fields into an array BEFORE calling
save or update_attributes:
unless params[:user].select{|k,v| k =~ /^favorite_colors_/}.empty?
params[:user][:favorite_colors] = params[:user].select{|k,v| k =~ /^favorite_colors_/}.values.reject{|v| v.empty?}
params[:user].reject! {|k,v| k=~ /^favorite_colors_/}
end
One thing I'm doing is to hard-code 10, which limits how many elements you can have in the favorite_colors array. In the form, it also outputs 10 text fields. We can change 10 to 100 easily. But we will still have a limit. Your suggestion on how to remove this limit is welcome.
Hope you find this post useful.
To allow access to AR attributes, you have to grant them like this:
class User < ActiveRecord::Base
serialize :favorite_colors, Array
attr_accessible :favorite_colors
....
end